Description: This function automatically deletes all materials that have no parts assigned to them.
Usage:
1. DSI deletes any unreferenced materials. If unreferenced materials are found, DSI shows the number of materials found and prompts:
> OK TO DELETE (1) UNREFERENCED MATERIALS? (Y/N)
If no unreferenced materials are found, DSI prompts:
> NO UNREF. MATERIALS FOUND